Tribuloside

Other Names

2-(4-Hydroxyphenyl)-3-[6-O-[3-(4-hydroxyphenyl)acryloyl]-β-D-glucopyranosyloxy]-5,7-dihydroxy-4H-1-benzopyran-4-one3-[6-O-[3-(4-Hydroxyphenyl)acryloyl]-β-D-glucopyranosyloxy]-5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one3-[[6-O-[3-(4-Hydroxyphenyl)-1-oxo-2-propenyl]-β-D-glucopyranosyl]oxy]-5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one5,7-dihydroxy-2-(4-hydroxyphenyl)-4-oxo-4H-1-benzopyran-3-yl 6-O-[(2E)-3-(4-hydroxyphenyl)prop-2-enoyl]-beta-D-glucopyranoside6''-O-trans-p-coumaroylastragalinAstragalin 6"-trans-p-coumarateKaem-3-Glc-6pp-p-CouKaempferol 3-O-β-D-(6"-O-(E)-p-coumaroyl)glucopyranosidekaempferol 3-O-β-D-glucopyranoside-6-p-coumaril esterKaempferol 3-β-D-(6"-p-coumaroyl)glucosideKaempferol-3-(p-coumaryl)glucosideKaempferol-3-Glucoside-6-p-coumaroylkaempferol-3-O-(6-p-coumaroyl)-glucosidekaempferol-3-O-beta-D-(6''-(E)-p-coumaroyl)-glucopyranosidePotengriffioside ATiliroside

Synopsis

Tribuloside: A Comprehensive Reference

1. Identity and Chemical Characterization

Chemical Name and Structure

Tribuloside is the trivial name for kaempferol-3-β-d-(6″-p-coumaroyl)glucoside, a flavonol glycoside first isolated from Tribulus terrestris. More precisely, it belongs to the acylated flavonoid glycoside class, meaning it consists of the flavonol aglycone kaempferol, a glucose sugar unit, and a p-coumaric acid moiety esterified at the 6″ position of the glucose. Tribuloside (numbered compound 130 in systematic reviews of T. terrestris phytochemistry) is one of several flavonoids with kaempferol as the basic parent structure identified in the plant.

The CAS Registry Number for tribuloside is 22153-44-2. Tribuloside is a flavonoid that has been found in T. terrestris and has been reported to possess antibacterial and antioxidant activities. It is sometimes encountered as a hydrate in commercial reference standards (tribuloside hydrate), and the SMILES and InChI structural identifiers confirm the coumaroyl-glucosyl-kaempferol connectivity.

Natural Sources

The primary botanical source from which tribuloside was first characterized is Tribulus terrestris L. (family Zygophyllaceae). Kaempferol, kaempferol-3-glucoside, kaempferol-3-rutinoside, and tribuloside (kaempferol-3-β-d-(6″-p-coumaroyl)glucoside) have been isolated from Tribulus terrestris. The compound is present in both the fruits and leaves of the plant. Bhutani et al. and Panova and Tomova were among the first researchers to report the presence of flavonoids such as kaempferol, kaempferol-3-glucoside, kaempferol-3-rutinoside, tribuloside, and rutin in T. terrestris leaves and fruits.

Tribuloside is not restricted to T. terrestris alone. Heritiera littoralis Dryand., a mangrove flora species, produces novel flavonoids including tribuloside, afzelin, and astilbin that were revealed to possess antimycobacterial activity against various species of nontuberculous mycobacteria (NTM). Important bioactive compounds such as rutin, kaempferol, quercetin, steroidal saponins, and tribuloside have been determined in tested T. terrestris extracts across multiple studies.

Common Forms and Preparations

The dietary supplement ingredient Tribulus is prepared from the leaves, root, and fruit of the Tribulus terrestris L. plant, which contains numerous chemical compounds, including steroidal saponins (plant steroids). Tribuloside itself is extracted as part of the total flavonoid fraction of T. terrestris. In research and commercial contexts, it is available as an isolated reference compound (including as a hydrate) for laboratory use. The plant material is processed into standardized herbal extracts — typically standardized to saponin content — in the form of capsules, tablets, powders, and liquid tinctures, within which tribuloside is one of multiple co-occurring bioactive flavonoids.

2. Botanical Context: Tribulus terrestris

Tribulus terrestris L. (TT) is an annual plant of the family Zygophyllaceae that has been used for generations to energize, vitalize, and improve sexual function and physical performance in men. The fruits and roots of TT have been used as a folk medicine for thousands of years in China, India, Sudan, and Pakistan.

Tribulus is a small, creeping plant that is native to the Mediterranean, Asia, and India, and is also found in the northern parts of Australia. It is well adapted to warm, dry climates and has been declared a noxious weed in many areas of North America. Commonly known as Gokshur, Gokharu, or puncture vine, the plant has been used for a long time in both the Indian and Chinese systems of medicine for the treatment of various kinds of diseases.

Various parts of the plant contain a variety of chemical constituents that are medicinally important, such as flavonoids, flavonol glycosides, steroidal saponins, and alkaloids. Saponins are a group of substances with various structures that consist of a hydrophobic aglycone and hydrophilic sugar residues (glycone), and they are usually divided into triterpenoid and steroid glycosides, or into triterpenoid, spirostanol, and furostanol saponins. There is a significant amount of research data about the species' chemical composition, specifically about the furostanol and spirostanol saponins found mainly in plants from China, Bulgaria, and India.

3. Traditional and Historical Use

Ayurvedic Tradition (India)

Tribulus terrestris L. is an important traditional therapeutic plant that has been utilized for multiple purposes since the Vedic period and belongs to the Zygophyllaceae family. In India, the fruits have been used in the treatment of infertility, impotence, erectile dysfunction, and low libido in Ayurveda. T. terrestris is used in various traditional medical practices — Ayurveda, Traditional Chinese Medicine, and Siddha — as a diuretic, aphrodisiac, immunomodulatory, anti-urolithic, antibacterial, anti-hyperlipidemic, antidiabetic, hepatoprotective, anticancer, anti-hypertensive, anthelmintic, analgesic, and anti-inflammatory drug.

Traditional Chinese Medicine (TCM)

In Traditional Chinese Medicine (TCM), the fruits have been used for treatment of eye problems, edema, abdominal distention, emission, morbid leucorrhea, sexual dysfunction, and veiling (a TCM term for visual disturbances). In native Chinese medicine, the leaves of Tribulus terrestris are also used for treatment of stomach problems, bladder stones, and male reproductive disorders. Within TCM, the plant is known by its Chinese name and is classified among remedies for the liver and kidney organ systems.

Other Traditional Systems

Tribulus has a long history of use as a herbal medicine by Chinese, Unani (Arabic), and Ayurvedic (Indian) systems of medicine. It is primarily used in these systems as a diuretic and in the treatment of kidney stones, urinary tract infections, and incontinence. It has also been used as a medicine in India, South Africa, and Japan.

In China, the fruits of Tribulus terrestris L. have long been utilized for relieving headache, dizziness, itchiness, and vitiligo. In ancient medicine, extracts of the aerial parts and fruits have been used for their diuretic, tonic, and aphrodisiac properties.

It is important to note that these traditional uses apply to Tribulus terrestris whole-plant preparations — not to tribuloside as an isolated compound. Tribuloside was first chemically characterized in 1969, making its identity as a discrete molecule a modern scientific development. Traditional remedies used decoctions, powders, and infusions of the whole fruit, leaf, or root, which contained tribuloside alongside many other constituents.

4. Phytochemical Context: Key Constituents of T. terrestris

Numerous bioactive phytochemicals, such as saponins and flavonoids, have been isolated and identified from TT that are responsible alone or in combination for various pharmacological activities. Modern research has revealed that the chemical components, viz., steroidal saponins and flavonoids, which have potent anti-inflammatory and antiaging characteristics, are the primary contributors to the traditional therapeutic activity of T. terrestris.

Among the basic flavonoids in TT are kaempferol, astragalin, kaempferol-3-rhamnoglycoside, tribuloside, and rutin. Tribuloside occupies a distinctive structural position within this flavonoid profile owing to its acylated (coumaroylated) sugar moiety, which differentiates it from simpler kaempferol glucosides such as astragalin (kaempferol-3-O-glucoside).

The high content of active ingredients — in particular sterol saponins, as well as flavonoids, tannins, terpenoids, phenol carboxylic acids, and alkaloids — and the plant's frequent use in folk medicine and as a food supplement highlight the importance of evaluating its phytopharmacological properties.

5. Mechanisms of Action

Antioxidant Activity

Tribuloside is a flavonoid that has been found in T. terrestris and has antibacterial and antioxidant activities. It scavenges DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals when used at concentrations ranging from 63.7 to 75.2 mg/ml. Tribuloside has 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. This free radical scavenging mechanism is characteristic of flavonols: the hydroxyl groups on the kaempferol nucleus can donate hydrogen atoms to neutralize reactive oxygen species (ROS).

Tribulosides have antioxidant capabilities, which help combat oxidative stress and cellular damage produced by free radicals. Some studies suggest that tribulosides may influence the immune system, although greater research in this area is needed.

Anti-Inflammatory Mechanisms

Tribuloside has anti-inflammatory properties and the ability to modulate the expression of inflammatory proteins and cell signaling pathways, presumably including the MAPK signaling pathway, which is critical in the inflammatory response. In the context of acute lung injury research, molecular docking analyses have identified key protein targets. Molecular docking with AutoDockTools found that tribuloside had a high affinity for IL6, BCL2, TNF, STAT3, IL1B, and MAPK3, the top six targets in the protein-protein interaction (PPI) network by degree values. The lowest binding energy was found between tribuloside and MAPK3, indicating the most stable interaction.

Pro-Melanogenic (Pigmentation) Mechanism

The inhibitory effect of tribuloside on phosphodiesterase (PDE) activity elevates intracellular cyclic adenosine monophosphate (cAMP) and activates protein kinase A (PKA). The activated PKA pathway ultimately promotes melanogenesis, melanocyte dendrite formation, and melanin transport without significant in vitro cytotoxicity. Water-based extract derived from Tribulus terrestris L. can enhance melanogenesis in mouse hair follicle melanocytes by elevating the expression of α-melanocyte stimulating hormone (α-MSH) and melanocortin-1 receptor (MC-1R).

Anticancer Mechanisms (Preclinical)

Tribulosides have also been investigated as anticancer agents, with the potential to inhibit tumor growth by influencing cell proliferation, apoptosis, and metastasis. These observations derive entirely from preclinical (in vitro and animal) work, and no human clinical trials on tribuloside's anticancer potential have been reported in the peer-reviewed literature to date.

Antimycobacterial Activity

Tribuloside is a flavonoid that can be isolated from Tribulus terrestris L. and exhibits anti-mycobacterial activity against non-pathogenic Mycobacterium species with a minimum inhibitory concentration (MIC) of 5.0 mg/mL. Research on tribuloside from the mangrove species Heritiera littoralis established specific MIC values: tribuloside is active against the mycobacteria M. madagascariense and M. indicus pranii (MICs = 0.8 and 1.6 mg/ml). These studies were conducted in vitro; no clinical antimycobacterial trials involving tribuloside have been published.

Effects on Cardiovascular Targets (In Silico)

In silico molecular docking and simulation for cardiac disease targets resulted in the identification of tribuloside among active ingredients against hub protein targets, suggesting these compounds could be potential lead compounds for treating cardiac diseases. A further assessment of efficacy can be made based on in vivo and in vitro studies for better understanding and stronger assertion. These findings are entirely computational and have not yet been validated in living systems.

6. Scientific Evidence by Area of Use

6.1 Acute Lung Injury (ALI)

Study type and design: One published study explored the mechanisms of action of tribuloside in treating ALI through a combination of network pharmacology and experimental validation. The researchers found 1,215 targets linked to ALI by examining the GeneCards database, and used the STRING database and Cytoscape software to create "drug or disease-target" networks as well as protein-protein interaction models. Key targets were identified by evaluating associated biological processes and pathway enrichment.

In vivo (animal) arm: To test tribuloside's therapeutic efficacy in ALI, an acute lung damage model in mice was constructed using lipopolysaccharide (LPS). Tribuloside treatment reduced inflammatory cell infiltration, decreased fibrotic area, repaired damaged alveoli, and suppressed inflammatory factors IL-6, TNF-α, and IL-1β in the lungs through multiple pathways and targets.

Pathway analysis: KEGG data analysis revealed that tribuloside treatment for ALI significantly enriched 49 target proteins over 162 signal pathways, indicating therapeutic potential across numerous pathways. The PI3K-AKT signaling pathway, which had the highest gene count enrichment among pathways, was identified as a relevant pathway in the therapy of ALI.

Evidence strength: This is preclinical (mouse model and in silico) evidence only, published in 2024. No human clinical trial on tribuloside and ALI exists. The methodology relies heavily on computational network pharmacology, a hypothesis-generating rather than confirmatory approach. The findings warrant follow-up in clinical settings but cannot be extrapolated to human efficacy.

6.2 Vitiligo and Melanogenesis (Skin Pigmentation)

Tribuloside, a natural flavonoid extracted from T. terrestris L., significantly promotes melanin synthesis in melanocytes, zebrafish, and human skin samples. Tribuloside acts on the PDE/cAMP/PKA pathway to enhance melanogenesis, melanocyte dendricity, and melanosome transport; meanwhile, tribuloside does not have any toxic effects on cells and may be introduced into clinical prescriptions to promote pigmentation.

T. terrestris L. shows promising multi-target activity in experimental models of vitiligo. Tribuloside, a natural flavonoid extracted from T. terrestris L., significantly promotes melanin synthesis in melanocytes, zebrafish, and human skin samples.

Evidence strength: Evidence includes in vitro (cell culture), in vivo (zebrafish model), and ex vivo (human skin sample) experiments, but no randomized controlled trials in human patients with vitiligo. The in vitro cytotoxicity findings (no significant toxicity) are preliminary. Clinical use should be considered investigational at this stage.

6.3 Antioxidant and Antimicrobial Activity

The antioxidant capacity of tribuloside has been established in vitro via DPPH scavenging assays. Tribuloside exhibits antibacterial and antioxidant activities, capable of scavenging DPPH free radicals. The antimycobacterial data from Heritiera littoralis-derived tribuloside are in vitro only, with MIC values in the milligram-per-milliliter range, which are pharmacologically high concentrations rarely achievable clinically.

Evidence strength: All antioxidant and antimicrobial data for tribuloside are in vitro. No animal models or human trials have evaluated these endpoints specifically for tribuloside as an isolated compound.

6.4 Reproductive Health and Aphrodisiac Effects

Tribuloside, a chemical compound identified in Tribulus terrestris, is thought to have pharmacological properties such as diuretic, hypotensive, anti-inflammatory, antioxidant, anticancer, and sexual function enhancing effects. However, human clinical trial evidence for aphrodisiac or sexual function-enhancing effects pertains primarily to whole-plant T. terrestris extracts — not to tribuloside as an isolated molecule.

In a relevant clinical trial of the parent plant: a study was designed as a randomized double-blind placebo-controlled trial to assess the safety and efficacy of Tribulus terrestris in women with hypoactive sexual desire disorder during their fertile years; sixty-seven women were randomly assigned to Tribulus terrestris extract (7.5 mg/day) or placebo for 4 weeks. This study used a standardized extract of the whole plant, not tribuloside, and its findings cannot be attributed to tribuloside alone.

Evidence strength: There is no clinical trial evidence for tribuloside specifically in reproductive health. Evidence for the whole-plant extract is mixed and methodologically limited.

6.5 Cardiovascular Health

In silico molecular docking and simulation resulted in the identification of tribuloside among active ingredients against hub protein targets involved in cardiac disease, and these compounds have been proposed as potential lead compounds for treating cardiac diseases. According to published evidence using whole-plant extracts, T. terrestris boosts testosterone secretion, regulates blood pressure, and protects the human body against injuries; the cardiovascular, reproductive, and urinary systems are all reportedly impacted.

Evidence strength: Evidence relating to tribuloside specifically in cardiovascular health is entirely in silico (computational docking). No in vitro, animal, or human evidence is available for tribuloside in isolation on cardiac outcomes.

6.6 General Pharmacological Profile (Whole-Plant Evidence)

The broader pharmacological profile most often attributed to T. terrestris preparations — which contain tribuloside as one constituent among many — spans numerous body systems. Reported activities include diuretic, aphrodisiac, antiurolithic, immunomodulatory, antidiabetic, absorption-enhancing, hypolipidemic, cardiotonic, central nervous system, hepatoprotective, anti-inflammatory, analgesic, antispasmodic, anticancer, antibacterial, anthelmintic, larvicidal, and anticariogenic effects. T. terrestris has been studied for its multiple therapeutic effects including immunomodulatory, aphrodisiac, anti-urolithic, absorption enhancer, cardioprotective, antidiabetic, anti-inflammatory, hypolipidemic, neuroprotective, anticancer, and analgesic properties. It must be emphasized that none of these broader activities have been attributed exclusively to tribuloside in peer-reviewed clinical research.

7. Body Systems and Health Areas

Respiratory system: Preclinical evidence (mouse LPS model) suggests tribuloside may attenuate acute lung injury by modulating inflammatory cytokines (IL-6, IL-1β, TNF-α) and the PI3K-AKT and MAPK pathways.
Integumentary/skin system: Tribuloside significantly promotes melanin synthesis and acts through PDE inhibition and cAMP/PKA elevation, making it relevant in the investigational context of vitiligo and hypopigmentation.
Cardiovascular system: Identified computationally as a candidate compound for cardiac disease targets; no clinical data exist for tribuloside specifically.
Reproductive system: Tribuloside is thought to have sexual function-enhancing effects, though evidence is based on whole-plant extract studies and pharmacological inference rather than isolated compound clinical trials.
Renal and urinary system: The parent plant has a long history of use as a diuretic and anti-urolithic agent in traditional medicine; whether tribuloside specifically contributes to these effects has not been established in isolation.
Immune system: Some studies suggest that tribulosides may influence the immune system, although greater research in this area is needed.
Microbiology: In vitro antimycobacterial activity has been demonstrated against several non-pathogenic Mycobacterium species.

8. Dosage Forms and Dosages Reported in Studies

Published scientific literature does not report standardized clinical dosages for tribuloside as an isolated purified compound, because no human clinical trials of isolated tribuloside have been conducted. Dosages reported relate to either:

Whole-plant or extract preparations used in human trials: In one randomized double-blind placebo-controlled trial, women with hypoactive sexual desire disorder were assigned to Tribulus terrestris extract at 7.5 mg/day for 4 weeks.
Animal model dosages: In a rat model investigating renal effects, animals were treated with T. terrestris hydroalcoholic extract at doses of 100, 200, and 300 mg/kg, administered orally for 7 days.
Preclinical toxicology: Acute oral toxicity studies established the median lethal dose (LD₅₀) to be greater than 2000 mg/kg body weight. No observed adverse effect level (NOAEL) by repeated oral toxicity for 28 days was established at 750 mg/kg body weight. These are animal figures and do not translate directly to human dosing.
In vitro concentrations: Tribuloside scavenges DPPH radicals when used at concentrations ranging from 63.7 to 75.2 mg/ml in cell-free assays — concentrations that are not clinically meaningful as systemic dosing targets.

Short-term studies on T. terrestris whole extracts (up to 3 months) have reported few adverse effects such as stomach cramps and nausea. Sleep disturbances, exhaustion, fatigue, and elevated heart rate have been reported after consuming more than 1,000 mg per day of the whole extract — a figure not attributable to tribuloside content specifically.

9. Safety Considerations and Drug Interactions

In Vitro Cell Safety

Tribuloside does not have any toxic effects on cells in vitro, as assessed in the melanogenesis study of 2024. This in vitro finding is encouraging but insufficient to characterize in vivo safety in humans.

Adverse Effects Reported with T. terrestris Preparations

Reported adverse effects pertain to whole-plant preparations consumed in dietary supplement form, not to tribuloside in isolation. The plant itself is known to be toxic to rats and sheep after ingesting large amounts, with effects including damage to the heart, liver, and kidneys. Research evaluating the safety of Tribulus in humans is limited.

A few cases of severe liver and renal (kidney) damage have been reported after individuals consumed supplements containing Tribulus. One documented case report described: neuro-, hepatic-, and renal toxicity suggestive of acute tubular necrosis (ATN) in a 28-year-old man who consumed large quantities of Tribulus extract for its antiurolithiatic properties. He additionally developed hypertension, seizures, and markedly elevated serum aminotransferases (>40× the upper limit of normal).

A further case involved: severe jaundice and hepatotoxicity, with a 46-year-old man who took Tribulus supplements daily for 2 months. Even after discontinuation of Tribulus for over 2 months, severe liver and renal injury persisted, and only improved after plasmapheresis was performed.

The steroidal saponin diosgenin is thought to be responsible for hepatotoxic effects associated with Tribulus. It is presently unclear what role, if any, the flavonoid tribuloside plays in these toxic presentations.

Neurological/Motor Adverse Effects

Consumption of Tribulus causes motor neuron adverse effects in animals by affecting the gamma-aminobutyric acid (GABA) receptors. This finding is from animal data and has not been systematically studied with isolated tribuloside.

Drug Interactions

Tribulus may increase the effects of other diuretic drugs. Clinical relevance is not known. No specific pharmacokinetic drug interaction data for tribuloside as an isolated compound are available in the peer-reviewed literature.

Safety in Clinical Studies of the Whole Plant

No significant abnormal changes in renal function biomarkers (creatinine, uric acid, urea, and BUN) were found in some clinical studies, and no drug-induced nephrotoxicity or hepatotoxicity was reported. However, no TT-induced toxicity was reported across a systematic review of seven studies in physically active adult males, though the authors noted methodological limitations and small sample sizes across the field.

Long-Term Safety

Research evaluating the safety of Tribulus in humans is limited. More research is needed to determine the safety of Tribulus as a dietary supplement ingredient, especially long term and in varying doses. No long-term safety data exist for tribuloside as a purified compound in humans.

10. Evidence Summary and Research Gaps

Tribuloside is a structurally well-characterized flavonoid glycoside with a growing, though still early-stage, body of preclinical research. Its most robustly documented in vitro properties are DPPH radical scavenging (antioxidant) and antimycobacterial activity. Its most advanced area of research is the investigation of its role in melanogenesis via the PDE/cAMP/PKA pathway, supported by in vitro, zebrafish, and human skin sample data. A 2024 network pharmacology and animal study explored its potential in acute lung injury.

There are miscellaneous hypotheses that T. terrestris species could have a high potential for the prevention and improvement of various human conditions such as infertility, low sexual desire, diabetes, and inflammatory diseases, but these are largely unconfirmed at the level of isolated tribuloside. Worldwide, numerous herbal supplements are commercialized with indications mostly to improve libido, sexual performance in both sexes, and athletic performance, yet the contribution of tribuloside specifically to these effects in commercial products has not been established.

Critical research gaps include: (1) no human clinical trials of isolated tribuloside for any indication; (2) no established pharmacokinetic profile (absorption, distribution, metabolism, excretion) in humans; (3) no established clinical dosing range; and (4) no systematic safety evaluation of tribuloside in isolation, as distinct from whole-plant extract preparations.

References

Health Conditions

Health conditions that Tribuloside may help support.

No conditions available.

Body Systems

Body systems that Tribuloside may help support.

No body systems available.